Trolling motor thrust vs boat size

[skunked again]

I have a g3 1756 dlx, with a 12v 40# mk edge, 50hp. Wanting to upgrade the tm. It does alright, once the breeze starts though, I'm on high speed. Currently have 2 27 series batts wired in parallel, so going to a 24v isn't a problem, switch some wires and I'm good to go.
Question is= would a 70# be to much? 55# enough? It would be nice to save some money, however, I don't want regrets, either way.
Also, can I use the existing 12v plug (2 wire) and wiring, if I go to a 24v tm?
I have done a little research, technically, the 40# is sufficient. Not in the real world though. I don't want to overpower it!

[KAG]

I am a big believer that too much TM does not exit. A 24v 70 would be great but the 24v 55 would do, I would not go 12v. You can find some Seriously good deals on used TM over at BBC

[Barnacle Bill]

You can't have to much as said but they don't make a 55 lb 24V anymore. A 70 would work great on that boat.

[RCC]

I ran a 55 Terrova on an Excel 1860vsc. I could spider rig all day on one battery and it would get to crank speeds just fine even loaded heavy. I never ran it at crank speeds for more than 2.5 hours so I don't know how long the battery would have lasted. I have just now replaced the 55 with a Terrova 80 just because I wasn't sure that long term the 55 would work out. If you are buying new and can afford it, I would go with the 80 even though the 55 may be adequate.

[speckfinder]

Get a variable speed and you can turn it down as slow as you need.

[wannabe fisherman]

called Minn-Kota once and asked them that question, they said 2lbs thrust for each foot of boat . That being said, I had a 55lb thrust on my 17' glass boat and in a 10mph wind it was hard to hold, went to an 80lb thrust and now I can go just fine. All this made me a believer that you should go as high in thrust as you can afford to.

[Drifty4]

you should go as high in thrust as you can afford to

You can't go wrong with a bigger motor.

As was said earlier, "you can always turn it down", but when full speed isn't enough, there is only one fix for that.

[Cray]

Either the 55/12 or 24/70-80 will work fine. Same battery set up on my Terrova 55 on 17.9 WarEagle. In a real strong wind I have to get it up to 6 to hold. Most of the time when it gets like that it's time to go home. Like someone else said if buying new I would spend the money for variable speed over the 5 speed edge. Much easier to control your speed and batteries will last much longer.
To your other question, yes you can use the same plug, just have to move your jumper on batteries to get 24. Everyone is going to recommend that if your wiring is not already 6 gauge to change it. If it is hard to get to and really difficult to change out your original wiring will work. The place where you would see your biggest drop would be on continues running like pulling cranks. Doubt you would ever see the difference on your boat.

[Cane Pole]

I put a 24v@80# thrust on my new boat which is 16 foot. However, my 40# MK pulled the boat just fine. I know what works best.

[Redge]

I am a big believer that too much TM does not exit. A 24v 70 would be great but the 24v 55 would do, I would not go 12v. You can find some Seriously good deals on used TM over at BBC

x2!